-Compat: Compatibility modes

Language

Application

-Compat[={!|=|c|s|f|$|a|b}

See below.

None

This option controls some compatibility enhancements of the Assembler. The goal is not to provide 100% compatibility with any other Assembler but to make it possible to reuse as much as possible. The various suboptions control different parts of the assembly:

• =: Operator != means equal

  The Assembler takes the default value of the != operator as not equal, as it is in the C language. For compatibility, this behavior can be changed to equal with this option. Because the danger of this option for existing code, a message is issued for every != which is treated as equal.

• !: Support additional ! operators

  The following additional operators are defined when this option is used:

  • !^: exponentiation
  • !m: modulo
  • !@: signed greater or equal
  • !g: signed greater
  • !%: signed less or equal
  • !t: signed less than
  • !$: unsigned greater or equal
  • !S: unsigned greater
  • !&: unsigned less or equal
  • !l: unsigned less
  • !n: one complement
  • !w: low operator
  • !h: high operator

    The default values for the following ! operators are defined:

       !.: binary AND

       !x: exclusive OR

       !+: binary OR

• c: Alternate comment rules

  With this suboption, comments implicitly start when a space is present after the argument list. A special character is not necessary. Be careful with spaces when this option is given because part of the intended arguments may be taken as a comment. However, to avoid accidental comments, the Assembler does issue a warning if such a comment does not start with a "*" or a ";".

The following listing demonstrates that when -Compat=c, comments can start with a *.

  NOP   * Anything following an asterisk is a comment.

When the -Compat=c assembler option is used, the first DC.B directive in the following listing, has "+ 1 , 1" as a comment. A warning is issued because the comment does not start with a ";" or a "*". With -Compat=c, this code generates a warning and three bytes with constant values 1, 2, and 1. Without it, this code generates four 8-bit constants of 2, 1, 2, and 1.

  DC.B 1 + 1 , 1
  DC.B 1+1,1

• s: Symbol prefixes

  With this suboption, some compatibility prefixes for symbols are supported. With this option, the Assembler accepts "pgz:" and "byte:" prefixed for symbols in XDEFs and XREFs. They correspond to XREF.B or XDEF.B with the same symbols without the prefix.

• f: Ignore FF character at line start

  With this suboption, an otherwise improper character recognized from feed character is ignored.

• $: Support the $ character in symbols

  With this suboption, the Assembler supports to start identifiers with a $ sign.

• a: Add some additional directives

  With this suboption, some additional directives are added for enhanced compatibility.

  The Assembler actually supports a SECT directive as an alias of the usual SECTION - Declare Relocatable Section assembly directive. The SECT directive takes the section name as its first argument.

• b: support the FOR directive

  With this suboption, the Assembler supports a FOR - Repeat assembly block assembly directive to generate repeated patterns more easily without having to use recursive macros.